FAQ
What is hydrogen?
The molecule of dihydrogen (H2) made up of two hydrogen atoms, is commonly called "hydrogen". The most abundant chemical element in the universe, hydrogen (H) is ranked first in the Mendeleiev table. It is the simplest and lightest atom: it consists of a nucleus containing a proton and a peripheral electron.
What are the benefits of hydrogen?
- Its combustion generates a large amount of energy (about 3 times more than gasoline at constant weight)
- Its combustion is non-carbonated (no CO2 emissions when it comes from renewable sources) and generates only water
- Hydrogen is very abundant on Earth in atomic form (water, hydrocarbons, etc.). Hydrogen also exists naturally (the first natural sources of hydrogen were discovered at the bottom of the sea in the 1970s and more recently on land)
- Hydrogen can be stored and is an efficient way to store electricity for long periods of time
What are the challenges in terms of energy transition?
ADEME identifies four challenges for the hydrogen vector in the coming years:
- In the context of a future electricity mix that strongly associates renewable sources, hydrogen brings flexibility and optimization solutions to energy networks. Power-to-gas, or the injection of hydrogen and/or synthetic methane, is a key way to connect electricity and gas networks
- Hydrogen provides new opportunities for self-consumption of local energy on the scale of a building, a block or a village, especially in areas not interconnected to the electrical grid
- The development of hydrogen electric vehicles is diversifying the electromobility offer, meeting the needs of professional mobility
- The new technologies allow to reduce the impacts linked to the current use of hydrogen of fossil origin in the industry
Why are we talking about green hydrogen?
Green hydrogen, produced mainly by electrolysis of water from renewable electricity, represents one of the levers of the future to accelerate the transition to carbon neutrality: development of green mobility, decarbonization of massive industrial uses of hydrogen (fertilizers, refineries, chemicals, etc.), better integration of intermittent renewable energies into the energy system, massive storage of surplus electricity produced.
Hydrogen can be used as a complement to all green energies to satisfy and decarbonize many uses and can become the pillar of 100% renewable territories.
Is hydrogen dangerous?
In its gaseous form, dihydrogen is very light. It is the only gas light enough to reach the upper layers of the atmosphere and escape into interstellar space. It has no color or odor, is non-toxic, is even used in gas mixtures in deep diving, but remains flammable in air. The explosive range of hydrogen is between 4% and 75% by volume of hydrogen in air, under normal pressure and temperature conditions.
For hydrogen to ignite, 3 conditions must be met simultaneously: the presence of a fuel, an oxidizer (oxygen) and sufficient activation energy (e.g. a spark). In order for hydrogen to explode, the 3 conditions linked to fire must be met (the presence of a fuel, an oxidizer and a source of ignition) but also a concentration of hydrogen that makes an explosion possible.
The H2Bordeaux project integrates the safety and prevention devices necessary to control these risks right from the design of the installations and ensures that safety is integrated into its operations at all levels.
What is the point of developing hydrogen electric mobility since battery electric vehicles already exist?
The two types of vehicles are complementary because they have different uses.
Because of their autonomy and recharging time (between 20 minutes - via a super charger, of which there are currently very few - and 8 hours), battery-powered vehicles are adapted to less intensive and regular urban use (no need to travel more than 120 kilometers in a day, even if only exceptionally).
For all drivers who use their vehicle more intensively and cannot afford to wait at a charging station, hydrogen electric vehicles are the most relevant answer.
Are hydrogen vehicles also zero-emission when analyzed on a life cycle basis?
No, but the rules to which all plants are subject make it possible to reduce emissions. Beyond that, the switch from natural gas-based hydrogen production to water electrolysis eliminates greenhouse gas emissions - the electrolyzer only emits heat and oxygen.
Most importantly, there is no pollution where hydrogen vehicles are used - which is not the case with internal combustion engines.
What are the different types of hydrogen?
The color approach to hydrogen is often ambiguous. Thanks to the Hydrogen Ordinance, the definition of different hydrogens focuses on the environmental attributes of hydrogen and no longer talks about colors.
- Renewable hydrogen, produced from renewable energy sources and whose production process respects a threshold of CO2 equivalent emissions per kilogram of hydrogen produced. This category includes electrolysis using renewable electricity (solar, wind, hydro), as well as any other production process using renewable energies and "not conflicting with other uses allowing their direct recovery" (pyrogasification or thermolysis of biomass, steam reforming of biogas)
- Low-carbon hydrogen, produced from non-renewable energy sources and respecting the same kgCO2eq/kgH2 threshold. Electrolysis powered by electricity from the French electricity mix would qualify, as well as processes combining carbon capture, sequestration or utilization (CCSU) techniques that can significantly reduce CO2 emissions at the plant gate
- Carbonaceous hydrogen is neither renewable nor low-carbon hydrogen. It includes fossil fuel-based production, such as hydrogen produced by steam reforming of natural gas (about 11 kgCO2/kgH2), by coal gasification (20 kgCO2/kgH2) or by electrolysis powered by carbon-based electricity mixes. But also potentially production from renewable energies that would not qualify for the emission threshold. This could concern, for example, hydrogen produced from biomass or biogas, depending on the nature of the inputs used and the associated carbon footprint, or even depending on the methane leaks taken into account upstream
What is the interest of hydrogen mobility?
Hydrogen can be used for all types of mobility and all types of vehicles. It is particularly relevant for intensive uses; forklifts are a very good example
The recharging time of a forklift equipped with a hydrogen fuel cell is a few minutes (compared to several hours for a battery-powered electric forklift)
Hydrogen is relevant for intensive uses, but also for heavy mobility: buses, trucks, garbage trucks, trains, barges, boats
What about the H2Bordeaux project?
It is relevant for port uses such as cranes and stackers.
It is also a very good energy carrier and can provide stationary uses (smoothing out consumption peaks, backup for installations, supplying electricity alongside the dock, etc.).
In order to prepare for the future, it will contribute to industrial uses by implementing new H2 activity zones on the docks in port areas.
What are the safety measures?
As with any industrial facility handling hazardous products, organizational and human factors will play a predominant role in the safety of these facilities. Staff training and the implementation of safety procedures (start-up, shutdown, maintenance, incident management) are two elements that are essential to their safety.
What are the economic benefits for France?
By 2050, decarbonated hydrogen could meet 20% of final energy demand and could reduce annual CO2 emissions by ~55 million tons, equivalent to one third of the additional CO2 reductions needed to close the gap between France's decarbonation targets (Climate Plan).
Decarbonated hydrogen and fuel cells would also create a full-fledged industry that would represent a turnover of about 8.5 billion euros in 2030, for more than 40,000 jobs, and would compensate for the possible loss of jobs today, particularly in the automotive sector. In 2050, this figure could reach 40 billion euros and over 150,000 employees.
The development of carbon-free hydrogen meets environmental, technological and economic challenges. It should enable France to accelerate the ecological transition, to be less dependent on hydrocarbon imports and to develop its technological assets.
What are the economic benefits for the Bordeaux region?
The project has echoed Europe with the co-financing of the H2Bordeaux project which will make it a showcase for the development of hydrogen in the port area with an economy born of hydrogen.